From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751682AbdJTA40 (ORCPT ); Thu, 19 Oct 2017 20:56:26 -0400 Received: from mail.kernel.org ([198.145.29.99]:46168 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751093AbdJTA4X (ORCPT ); Thu, 19 Oct 2017 20:56:23 -0400 DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 81A0421922 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=frederic@kernel.org From: Frederic Weisbecker To: LKML Cc: Frederic Weisbecker , Tejun Heo , Peter Zijlstra , "David S . Miller" , Lai Jiangshan , Thomas Gleixner , "Paul E . McKenney" , Ingo Molnar Subject: [PATCH 01/14] lockdep: Add IRQs disabled/enabled assertion Date: Fri, 20 Oct 2017 02:55:58 +0200 Message-Id: <1508460971-8731-2-git-send-email-frederic@kernel.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1508460971-8731-1-git-send-email-frederic@kernel.org> References: <1508460971-8731-1-git-send-email-frederic@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Checking whether IRQs are enabled or disabled is a very common sanity check, however not free of overhead especially on fastpath where such assertion is very common. Lockdep is a good host for such concurrency correctness check and it even already tracks down IRQs disablement state. Just reuse its machinery. This will allow us to get rid of the flags pop and check overhead from fast path when kernel is built for production. Suggested-by: Peter Zijlstra Signed-off-by: Frederic Weisbecker Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Thomas Gleixner Cc: Paul E. McKenney --- include/linux/lockdep.h | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/include/linux/lockdep.h b/include/linux/lockdep.h index bfa8e0b..fbe0127 100644 --- a/include/linux/lockdep.h +++ b/include/linux/lockdep.h @@ -719,9 +719,22 @@ do { \ lock_acquire(&(lock)->dep_map, 0, 0, 1, 1, NULL, _THIS_IP_); \ lock_release(&(lock)->dep_map, 0, _THIS_IP_); \ } while (0) + +#define lockdep_assert_irqs_enabled() ({ \ + !WARN_ONCE(debug_locks && !current->hardirqs_enabled, \ + "IRQs not enabled as expected\n"); \ + }) + +#define lockdep_assert_irqs_disabled() ({ \ + !WARN_ONCE(debug_locks && current->hardirqs_enabled, \ + "IRQs not disabled as expected\n"); \ + }) + #else # define might_lock(lock) do { } while (0) # define might_lock_read(lock) do { } while (0) +static inline int lockdep_assert_irqs_enabled(void) { return 1; } +static inline int lockdep_assert_irqs_disabled(void) { return 1; } #endif #ifdef CONFIG_LOCKDEP -- 2.7.4